Nature of problem:The heavy lepton tau decays into two pure leptonic and many hadronic
decay channels. They can be used to study the corresponding elements of
the charged current or, as a tool in testing electroweak theory. In
particular, since the distributions of the tau decay products are
sensitive to tau polarization, they are used as spin polarimeters.

Solution method:The Monte Carlo simulation is suited best for studying tau decays,
because typically tau may decay into several particles and the decay
distributions are difficult to handle analytically. Furthermore, many
Monte Carlo programs for tau production exist already and they must
include high quality subprograms for tau decays.

Restrictions:For decays into four and more pions a simplified dynamical treatment has
been adopted.